1. Field of the Invention
The present invention relates generally to flexible hoses, and in particular to a flexible hose with a length control adhesive strip.
2. Description of the Prior Art
Flexible hoses are well known and various configurations have been devised for particular applications. A common type of flexible metal hose is formed by spiral-winding a continuous metal band and interlocking the leading and trailing edges thereof Such a manufacturing process is disclosed in the McGowen U.S. Pat. No. 4,197,728.
A common application of flexible metal hose is in vehicle exhaust systems, particularly where the hose is subjected to vibration, thermal stress and relative movement between the components connected thereby. For example, in the exhaust systems of tractor units of tractor trailer rigs an exhaust manifold is typically connected to an exhaust pipe by a flexible connection to absorb some of the relative movement and vibration referred to above. Such systems are typically designed with relatively precise design or engineered lengths. Manufacturing techniques exist for producing flexible hoses with such predetermined design engineered lengths. For example, the flexible hose can either be stretched or compressed as necessary. A predetermined design length specification can be met by winding the flexible hose relatively tightly. However, overly tight windings tend to greatly restrict flexibility, and can lead to premature wear and failure due to the inability of the windings to shift relative to each other.
Accordingly, there is a need for a flexible hose construction with a length control feature. Heretofore, there has not been available a length-controlled flexible hose and method of manufacturing same with the advantages and the features of the present invention.
In the practice of the present invention, a flexible hose is provided for connecting the components in, for example, an exhaust system. The flexible hose includes first and second ends and first and second end sections located adjacent to the ends. A medial section of the flexible hose is located between the end sections. The flexible hose is formed by spiral-winding a continuous metal band with interlocked leading and trailing edges. Helical channels are formed between the interlocked band edges and are open at inner and outer surfaces of the flexible hose. The interlocked leading and trailing edges accommodate a limited amount of movement whereby flexibility is provided with the hose. The length of the hose is controlled by placing one or more length control adhesive strips along one or both of the flexible hose surfaces. Each length control strip forms spacers located within a channel along one surface of the hose. The spacers maintain a predetermined spacing of a channel along a respective flexible hose surface and thus maintain a design or engineered length of the flexible hose, which can be determined, for example, by the spacing of the exhaust system components which it connects. A length control adhesive strip can assume different configurations on a surface of the flexible hose. In the practice of the method of the present invention, a design length for the flexible hose is determined in relation to the spacing of components which it connects. A metal band is spiral wound and produces a flexible hose with helical channels open at surfaces thereof A length control adhesive strip is applied to the flexible hose and forms spacers within a channel thereof, which maintain the engineered or design length of the hose.
The objects and advantages of the present invention include: providing a flexible metal hose with a length control adhesive strip; providing such a flexible hose which maintains a predetermined, design or engineered length in shipping, handling and installation; providing such a flexible hose which facilitates the installation process; providing such a flexible hose which can maintain a predetermined length relative to an exhaust system in which it is installed; providing such a flexible hose which can be manufactured with existing or readily available equipment, providing such a flexible hose which can accommodate various numbers and configurations of length control adhesive strips; providing a method of manufacturing a flexible metal hose which produces a length-controlled flexible hose; providing such a method which accommodates a wide variety of applications; and providing a length-controlled flexible hose and method of manufacturing same which are efficient in operation, economical and particularly well adapted for the proposed uses thereof.
Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention.
The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof